Evolution mechanisms of texture and microstructure during recrystallization of ferritic steel sheets

Abstract

The formation of recrystallization microstructure and texture in ferritic steel sheets used in the automotive industry is presented and involved mechanisms are discussed in connection with the substructure formed during the deformation preceding the annealing. Nucleation principally happens in the gamma-fibre grains, which develop smaller deformation cells and higher local misorientations than the alpha-fibre grains. The development of the nuclei is then analyzed by analogy with the abnormal coarsening which sometimes occurs after recrystallization. Finally, some relations between recrystallization textures / microstructures and mechanical properties are shown, like the effect of the rolling level on the anisotropy or the decrease of mechanical properties when under-recrystallisation happens.